The net emissions number is what the CER compares with a facility’s baseline. It starts with the facility’s covered emissions and is adjusted for carbon units.
Key points
- Starts with covered emissions from the NGER report
- Surrendered ACCUs and SMCs are subtracted
- Attributable ACCUs are added back
- Prevents double counting of the same reduction
- Usually calculated per financial year
The four steps
- Start with total covered emissions in the facility’s NGER report.
- Subtract all ACCUs and SMCs surrendered for the facility.
- Add any ACCUs issued in the monitoring period for abatement of the facility’s covered emissions (attributable ACCUs).
- Subtract any attributable ACCUs deemed surrendered by delivery under an eligible carbon abatement contract.
Why attributable ACCUs are added back
If a project at a Safeguard facility earns ACCUs for cutting that facility’s covered emissions, the same reduction already lowers the facility’s reported emissions. Adding one tonne for each attributable ACCU stops the reduction being counted twice.
Deemed surrender
Attributable ACCUs delivered under a carbon abatement contract formed before 30 March 2023 that names the project are treated as surrendered and subtracted.
The monitoring period
The calculation is usually done for a financial year. It can cover a longer multi-year monitoring period, or part of a year when operational control changes.
A worked illustration
Take a facility with covered emissions of 1,200,000 t CO2-e. It surrenders 50,000 ACCUs and 30,000 SMCs, and a project at the facility was issued 10,000 attributable ACCUs. Its net emissions number is 1,200,000 less 80,000 plus 10,000, or 1,130,000 t CO2-e. Against a baseline of 1,150,000 t CO2-e, there is no excess. The figures are illustrative only.
Where covered emissions come from
Covered emissions are taken from the facility’s NGER report, lodged by 31 October and prepared under the Measurement Determination for that reporting year. Any correction to the NGER report flows through to the net emissions number, and the CER tracks facilities that fall into excess because of resubmitted NGER data.
Net emissions and SMCs
SMC entitlements use a related but separate calculation: the baseline less covered emissions less any ACCUs issued for the facility in the monitoring period.
References & sources
Primary regulatory documents and authoritative references underpinning this answer.